Enhanced Photoreduction Activity of Carbon Dioxide over Co₃O₄/CeO₂ Catalysts under Visible Light Irradiation

Figure 9

XPS spectra of (a) the Co 2p region and (b) the Co 3s-Ce 4d region for 5 wt.% Co₃O₄/CeO₂ prepared by calcining the spontaneous combusted precursor at temperatures 300°C, 400°C, and 500°C.

(a)

(b)